Digital clock display

ABSTRACT

An opaque face plate has openings arranged in rectangular arrays, with each array representing one digit of a multi-digit number. A light source is mounted behind the face plate and an opaque, orbitally movable plate is mounted between each rectangular array of openings and the light source. Each orbitally movable plate has sets of orbitally arranged openings so that each opening, when moved into alignment with a corresponding opening in the array of openings, will transmit light through that opening in the faceplate. The geometrical pattern of light transmission through each orbitally movable plate is arranged to produce a time sequence of digits in each of the rectangular arrays of openings so that the invention may function as an illuminated digital clock. Drive means is coupled to the orbitally movable plates to drive the plates in predetermined correlation around their respective orbits. A transparent light-diffusing element may be wound over each opening in the face plate to spread the light transmitted through the openings and make the openings appear larger than they actually are.

United States Patent [1 1 Trame [54] DIGITAL CLOCK DISPLAY [75] Inventor: Charles E. Trame, Fox Point, Wis.

[73] Assignee: Everbrite Electric Signs, Inc South Milwaukee, Wis.

[22] Filed: June 14, 1972 [21] Appl. No.: 262,690

[52] US. Cl. 40/28 C, 58/50 R, 40/l06.53,

40/l06.53, 28 R, 106.51, 130 R, 130 E, 132

G; 58/1 R, 2,4R,4A,4M, 45, 50 R, 125 R,-

125 B, 125 C, 152 R, 152 A, 152 F, 152 G,

[56] References Cited I UNITED STATES PATENTS 1,923,523 8/1933 Whitney 40/28 C 2,151,236 3/1939 Schwartz et 31 40/28 C 1,114,267 10/1914 101168 40/28 C 2,371,172 3/1945 Hotchner lo/106.53 3,054,203 9/1962 French 40/28 C 3,399,474 9/1968 Rinder 40/28 C 3,681,917 8/1972 Kroeger 58/125 B 11] 3,783,539 [451 Jan. 8, 1974 Primary Examiner-Richard B. Wilkinson Assistant Examiner-U. Weldon Attorney-Arthur L. Morsell, Jr.

[5 7] ABSTRACT An opaque face plate has openings arranged in rectangular arrays, with each array representing one digit of a multi-digit number. A light source is mounted behind the face plate and an opaque, orbitally movable plate is mounted between each rectangular array of openings and the light source. Each orbitally movable plate has sets of orbitally arranged openings so that each opening, when moved into alignment with a corresponding opening in the array of openings, will transmit light through that opening in the faceplate. The geometrical pattern of light transmission through each orbitally movable plate isv arranged to produce a time sequence of digits in each of the rectangular arrays of openings so that the invention may function as an illuminated digital, clock. Drive means is coupled to the orbitally movable plates to drive the plates in pre-v determined correlation around their respective orbits. A transparent light-diffusing element may be wound over each opening in the face plate to spread the light transmitted through the openings and make the openings appear larger than they actually are.

3 Claims, 6 Drawing Figures PATENTED 81974 3,783,539

' sum 1 0f 3 ISM C, Z @222 a 1 DIGITAL CLOCK DISPLAY BACKGROUND OF THE INVENTION In the past, digital numerical displays or letter displays have been proposed which make use of arrays of light bulbs together with electrical switch means for activating predetermined geometrical patterns of the light bulbs in a predetermined manner. Such digital displays have been used in advertising displays which featured a sequential verbal message, or the time of day, temperature, or the like. Although these displays have been quite effective, their use in the past has been limited by the high cost of the multitude of light bulbs required, by the difficulty of locating and replacing burned-out bulbs, and by the complicated switchingcircuitsthat are required to effect the sequential switching of the light bulbs.

Accordingly, one principal object of the invention is to provide a digital display device that does not require electrical switching circuits but, instead, utilizes a relatively simple mechanical movement.

Another object of this invention is to provide a digital display device of the above noted type which is capable of accurately displaying the time of day.

A further object of the invention is to provide a digital display device which does not require a plurality of I light bulbs but which may be activated by a single light bulb.

An additional object of this invention is to provide a digital display device which is relatively simple in structure, inexpensive in cost, and reliable in operation.

SUMMARY OF THE INVENTION In accordance with this invention, the above noted objects are achieved by providing a light source, an opaque face plate mounted in front of the lightsource with at least two arrays of openings in the face plate, a plurality of orbitally movable plates, the orbitally movable plates being mounted between the face plate and the light source opposite a corresponding array of openings and having orbitally arranged openings therein, each opening being positioned to admit light to a corresponding opening in the face plate when the orbitally movable plate is in a predetermined orbital position. The arrays of openings in the face plate are arranged to represent a plurality of different characters when light is transmitted through a predetermined grouping of the openings. The openings in the orbitally movable plates are arranged to selectively transmit light from the light source through predetermined groupings of openings in the arrays to produce a predetermined sequence of characters as the orbitally movable plates are moved around their orbits. Means are provided for mechanically driving the orbitally movable plates around their orbits in correlated timing to produce predetermined sequences of multiple character displays. In order to enhance the visibility of the display, a light diffusing element may be mounted over each opening in the face plate to make each opening appear to be larger than it really is.

In the preferred embodiment of the invention, the display is a series of numerals that signify the time of day.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic exploded perspective view showing the light source, face plate, and orbitally movable plates of one illustrative embodimentof the invention;

FIG. 2 is an enlarged plan view of a portion of one of the orbitally movable plates shown in FIG. 1 showing the orbitally arranged openings therein;

FIG. 3 is an elevational view of a mechanical mechanism for driving a set of orbitally movable plates through their orbital movements;

FIG. 4 is a cross-sectional plan view taken on the line 4-4 of FIG. 3;

FIG. 5 is a side elevational view of the embodiment illustrated in FIGS. 3 and 4, parts of the plates being broken away and shown in section; and

FIG. 6 is an enlarged detail sectional view taken on the line 6-6 of FIG. 3.

DETAILED DESCRIPTION OF THE INVENTION Referring to FIG. 1, the basic units of one illustrative embodiment of the invention are diagrammatically shown in exploded perspective form. These basic units include a fluorescent lamp 20, a curved reflector 22 for reflecting the light from the lamp 20 over a relatively large rectangular surface, an opaque rectangular face plate 24 which has openings 25 formed therein and arranged to form three rectangular arrays of openings 26, 28, and 30-32, and three orbitally movable plates 34, 36, and 38 which are mounted between the face plate 24 and the light bulb 20. The array 30-32 is a two-part array as will be hereinafter explained.

The arrays of openings in theface plate 24 are rectangular in this particular embodiment of the invention but might be of other shapes,-and each of the arrays 26, 28, and 30 is adapted to display any one of the digits 0 through 9 by passing light through selected groupings of the openings 25. For example, to representthe numeral 1, one vertical column of the openings will have light admitted therethrough while the other vertical columns of openingswill be blocked. For the other numerals, the appropriate geometrical configuration will be apparent to those skilled in the art.

This particular embodiment of the invention is a digital clock for displaying the time of day, wherein the array of openings 26 represents the minute digit, the array of openings 28 represents the 10-minute digit, and the two-part array 30-32 taken together represent the hour digit ordigits. Since there are only twelve hours in civilian clocks, the last digit which is represented by array part 32 will be only the presence or absence of the numeral 1 and, hence, this array part is composed of merely one vertical column of light openings.

The orbitally movable plates 34, 36, and 38 which are positioned between the face plate 24 and the light source 20-22 have orbitally arranged sets of openings 39 therein for admitting light'throu'gh predetermined geometrical configurations of openings in the face plate 24 to produce the above noted digital figures representing the time of clay.

FIG. 2 shows a detail plan view of the orbital openings on the orbitally movable plate 38 for producing the hour digits. Each opening of each circle of openings 39 is alignable with one and only one opening 25 in the face plate 24. Openings around the circle which are not in alignment at a particular time are in other orbital positions and are movable to an orbital position ofalignment with the face plate opening. The numerals adjacent the openings in the plate 38 (FIG. 2) designate those openings which, when moved to positions of alignment with the openings 25 of the face plate, will allow light from the source 20 to shine through the face plate and create the particular numeral identified in FIG. 2. Thus it will be noted that the orbital openings in the row at the left of FIG. 2 which correspond to the array part 32 on the face plate, contain three openings which are alignable with the corresponding openings 25 on the face plate 24 in the tenth, eleventh, and twelfth orbital positions of the orbitally movable plate 38 to produce the numeral 1 only at a time when the hour reading on the clock is 10, 11 or 12. This, of course, reflects the fact that the 1 is displayed in array part 32 for the tenth, eleventh, and twelfth hours only, and in all other orbital positions the orbitally movable plate 38 blocks the light through all of the openings in the array 32 of the face plate as no number 1 in the array 32 is required for single digit numbers in the hour portion of the clock.

The array part 30 is somewhat more complicated, but it is designed along these same lines. Referring again to FIGS. 1 and 2, it will be seen that there is one circle of orbitally disposed openings 39 in the orbitally movable plate 38 of FIG. 2 for each single opening 25 in the array part 30. In the example shown in FIG. 2, the geometric pattern formed by the openings for the twelfth orbital position is made clearer by darkening the corresponding openings. It will be seen that the openings marked 12 on the left hand side produce a straight line which produces the digit 1, andin the four vertical columns of openings on the right, which comprise the array part 30, the openings 12 trace a curved path which produces the digit 2.

The spaced circle of openings 39 in the orbitally movable plate 38 are arranged to produce the numbers 1 through 12in sequence as the plate is moved through its orbital positions one through twelve. The particular openings in the face plate 24 which will be open to admit light therethrough correspond to those which are indicated by the numerals adjacent the openings in FIG. 2. An example for the number 12 has been given above in the twelfth position of the orbitally movable plate 38. When the plate 38 moves from the twelfth position to the first position, all of the openings marked 1 in FIG. 2 will align with all of the openings in the right hand vertical row of the array 30, and all of the other openings will be out of alignment and the panel 38 will block light. It will be noted that all of the openings marked 1 in FIG. 2 alignwith the right-hand vertical column of openings in the face plate 24, which means that only the, right-hand vertical column of openings will have light passing through in the array 30-32. This represents the numeral 1. In the second through twelfth orbital position of the orbitally movable plate 38, the geometric configuration follows the numbers shown in FIG. 2 to give the corresponding geometrical shape of the required hour digit.

The orbitally movable plates 34 and 36 are similar to plate 38 in construction, although since they need to cover only six digits through 5) and digits (0 through 9) respectively, instead of 12, there would be only six orbital positions for the plate 36 and ten orbital positions for the plate 34. Also, the orbital plates 34 and 36 would be driven through one complete orbit in a 10-minute and a l-hour cycle, respectively, instead of for the l2-h0ur cycle required for the orbitally movable plate 38. The timing of the cycles will be discussed in greater detail in connection with the driving means for driving the orbitally movable platesl plates 34, 36, and 38 diagrammatically, it is apparent that means are required for supporting the plates for motion in an orbital path and also for driving the plates in predetermined synchronism to produce the digital numbers indicating the time of day. FIGS. 3, 4, 5, and 6 indicate one illustrative mechanical means of achieving the above noted objectives. Referring to FIG. 3, three orbitally movable plates 34', 36, and 38 are suspended for orbital movement by means of upper crank members 40, 42, 44, and 46, and lower eccentric pins 56, 58 and 60 which act as drive members for the orbitally movable plates 34', 36', and 38', and which will be discussed later. Only a few of the openings for the plates 34, 36', and 38' are shown in FIG. 3, it being understood that the openings are the same as has heretofore been described in connection with FIGS. 1 and 2. The upper cranks 40, 42, 44, and 46 are pivotally attached at one end to projecting tabs 48, 50, 52, and 54 which project upwardly from the orbitally movable plates 34', 36, and 38'. The other ends of the cranks, 40, 42, 44, and 46 are pivotally attached to the rear of the upper margins of a front plate 24, as indicated for the crank 40 in FIG. 5, at the numeral 56. The tabs 48, 50, 52, and 54 are recessed out and away from the crankarms 40, 42, 44, and 46 so that the cranks can be swung completely around without interference.

Before describing the orbital drive which is attached to the orbitally movable plate 34', it will be helpful to review the requirements for the movement of each of these plates. Orbitally movable plate 34', which corresponds to orbitally movable plate 34 described above, produces the last digit of the time of day number, i.e., the number of minutes. Accordingly, the character which will be displayed through the orbitally movable plate 34 must be indexable through ten positions so as to display the numerals 0 through 9 and must be indexed from one position to the next every minute. In other words, the orbitally movable plate 34' must be moved through approximately 36 every minute on the minute. There will be orbital groupings like that on the I right hand side of FIG. 2, but the number of openings in each orbital grouping will vary and will be arranged to display the minute digits as above explained.

The next orbitally movable plate 36', corresponding to the plate 36 of FIG. 1, has to be indexed by one position for every ten minutes from 0 to 60. This requires that the orbital movement of plate 36' should have six indexable positions of 60 each to cause the display of the digits 0 through 5, and that the plate should be indexed from one position to the next every 10 minutes on the minute. The remaining orbitally movable plate 38 is similar to the plate 38 shown in FIGS. 1 and 2, and it must have 12 indexable positions of 30 each which are indexed every hour on the hour to display the numerals 1 through 12.

The orbitally movable plates 34, 36, and 38 are driven around their orbit from below by means of eccentric pins 56, 58, and 60 (FIG. 4) which are eccentrically mounted on bevel gears 62, 64, and 6 6. The pins 56, 68, and 60 project from the corresponding bevel gear and are attached to downwardly projecting tabs 68, 70, and 72. The crank radius of eccentric pins 56, 58, and 60 is the same as the crank radius of crank arms 40, 42, and 44-46 from which the orbitally movable plates are suspended on their upper edges. Thus, as the bevel gears 62, 64, and 66 are rotated the orbitally movable plates 34', 36', and 38' are driven around in an orbit which is determined by the crank radius of the crank pins 40, 42, 44-46, and the crank radius of the eccentric pins 56, 58, and 60.

The drive source for the unit consists of an electric motor 74 having a shaft 76 upon which is carried a wheel 78 having an intermittent drive pin 80 for coaction with the notched hub 82 of a bevel gear 84. The hub 82 of bevel gear 84 is joumalled about the axis of a shaft 85 which is supported at its ends on fixed frame portions 83. The bevel gear 84 engages'bevelgear 62, whereby the two gears rotate together. The shaft 76 is rotated at a speed of one revolution per minute by the motor 74, which means that the wheel 78 and intermittent drive pin 80 will make one revolution per minute. Referring to FIG. 6, this means that the intermittent drive pin 80 will engageone of the ten radial notches 79 (FIG; 6) in the hub 82 and move the hub 82 through an angle of 36 before becoming disengaged from a notch 79. The hub 82 will, therefore, be intermittently engaged and moved through a 36 arc every minute on the minute, and this will cause the bevel gear 84 to rotate through the same arc every minute on the minute, which in turn drives the bevel gear 62.

In order to provide for hand-setting of the mechanism, the wheel 78 is slideably splined to the shaft 76, and although it is normally biased outwardly by a spring 86, it can be moved against the force of the spring 86 by a manual clutch handle 88 to temporarily disengage the intermittent drive pin 80 from the hub 82. An enlarged hand wheel 90, which projects below the frame as in FIG. 3, is attached to the bevel gear 62. By turning the lower portion of this wheel by hand, the mechanism, such as a clock, may be set.

A sleeve 92 is attached to the hub 82 and rotates therewith. A wheel 94 carrying an intermittent drive pin 96 is attached-to the end of the sleeve 92. The sleeve 92 is rotated intermittently along with the bevel gear 84 so as to complete one full revolution every ten minutes. Six notches 93 are cut in the hub 98 and the intermittent drive pin 96 engages the notches 93 in hub 98 so as to advance the hub 60 for every complete revolution of the intermittent drive pin 96. This drives bevel gear 64 at a rate of one revolution per hour.

The bevel gear 100 is journalled about the axis of a shaft 102, and a sleeve 104 is attached to the hub 98. A wheel 106 carrying an intermittent drive pin 108 is attached to the end of sleeve 104. The intermittent drive pin 108 engages notches 105 formed in a cylindri cal projection 110 of a bevel gear 112, which gear engages the bevel gear 66. There are twelve notches 105 in the cylindrical projection 110 representing 12 hours and the intermittent drive pin 108 engages one of the notches 105 in the member 110 every hour on the hour and moves the member 110 through a 30 arc. Twelve of these 30 arcs equal 36.

The above-described mechanical drive members are mounted upon a base plate 114 which has upwardly projecting brackets 116 for supporting the various parts of the mechanism. Although the lamp and reflector 22 are only shown in FIG. 1, it is obvious that a similar lamp and reflector must be mounted on the right hand side of the base 114 of FIG. 5 to illuminate the back of the orbitally movable plates 34', 36', and

38. Any one or more sources of light may be employed.

The openings in face plate 24' (FIG; 5) can be flush with the outer surface of the face plate if desired, but in the preferred embodiment of the invention a novel arrangement of hemispherical recesses 118 is employed, which support-lenses B20. The lenses 120 act as a light diffusing element which spreads the light transmitted through the small openings 25' and makes them appear larger than they actually are.

It is preferred to utilize counterbalancing wind-up springs (FIG. 3) which are suitably supported from the frame and which have wind-up spring tapes 131 connected to the orbitally movable panels as shown. When the panels move downwardly they will pull on the wound tapes 131. Then when the panels are ready to move upwardly the spring wind mechanism in the members 130 will act through the tapes to urge the panels upwardly and thus relieve the motor 74.

From the foregoing description it will be apparent that this invention provides a digital display device that does not require a complicated electrical switching circuit, but is instead operated by a relatively simple mechanical movement. And, although this invention has been illustrated with reference to. one specific embodiment thereof, it should be understood that the invention is by no means limited to the disclosed embodiment since many modifications can be made in the disclosed structure without changing its basic principles of operation. Many of such modifications will be apparent to those skilled in the art, and this invention includes all such modifications as may fall within the scope of the following claims.

What is claimed is:

1. A display device comprising a light source, an opaque face plate mounted in front of said light source, at least two arrays of openings formed in said face plate, each of said arrays of openings being arranged to represent characters when light is transmitted through a predetermined grouping of said openings, a plurality of movable opaque plates arranged edgewise of one another in row formation and each positioned behind a cooperative array of openings in the face plate, means mounting each of said movable plates for orbital movement betweensaid light source and said cooperative array of openings of the face plate, each of said orbitally movable plates having a plurality of differently arranged sets of orbitally arranged openings therethrough, each opening of a set of orbitally arranged openings being alignable with one opening of the cooperative array of openings in said face plate and being positioned at a predetermined orbital position to admit light to an aligned opening in said face plate depending upon the position of the movable plate, whereby the aligned openings of the sets produce a different character for each of said orbital positions, and; means for orbitally moving said orbitally movable plates at different rates of speed but in correlation with each other to produce a predetermined sequence of characters in each array of openings in said face plate.

2. A display device as claimed in claim 1 in which the means for orbitally moving said orbitally movable movable plates are disposed in vertical planes and wherein there is spring means connected with each movable plate in a position to aid the drive means when a plate is being moved'in a direction against the force of gravity. 

1. A display device comprising a light source, an opaque face plate mounted in front of said light source, at least two arrays of openings formed in said face plate, each of said arrays of openings being arranged to represent characters when light is transmitted through a predetermined grouping of said openings, a plurality of movable opaque plates arranged edgewise of one another in row formation and each positioned behind a cooperative array of openings in the face plate, means mounting each of said movable plates for orbital movement between said light source and said cooperative array of openings of the face plate, each of said orbitally movable plates having a plurality of differently arranged sets of orbitally arranged openings therethrough, each opening of a set of orbitally arranged openings being alignable with one opening of the cooperative array of openings in said face plate and being positioned at a predetermined orbital position to admit light to an aligned opening in said face plate depending upon the position of the movable plate, whereby the aligned openings of the sets produce a different character for each of said orbital positions, and means for orbitally moving said orbitally movable plates at different rates of speed but in correlation with each other to produce a predetermined sequence of characters in each array of openings in said face plate.
 2. A display device as claimed in claim 1 in which the means for orbitally moving said orbitally movable plates comprises the following: a bevel gear for each movable plate positioned in parallelism therewith, means including an eccentric pin projecting from each bevel gear for causing the orbital movement of its plate, a second bevel gear at right angles to and engaged with the first bevel gear for each plate, means for driving one of said second bevel gears at a predetermined rate of speed, and means for transmitting movement from said last-mentioned bevel gear to the second bevel gear for another orbitally movable plate for driving the latter at a different rate of speed.
 3. A display device as claimed in claim 2 wherein the movable plates are disposed in vertical planes and wherein there is spring means connected with each movable plate in a position to aid the drive means when a plate is being moved in a direction against the force of gravity. 